oalib
Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
离子液体[Bmim]PF6萃取处理硝基酚废水  [PDF]
付宏权,刘培元,陈盈,林金清
华侨大学学报(自然科学版) , 2013, DOI: 10.11830/ISSN.1000-5013.2013.03.0303
Abstract: 以1-甲基咪唑、氯代正丁烷和六氟磷酸钾为原料,采用两步法制备了疏水性离子液体[Bmim]PF6,并用红外光谱及核磁共振对其进行了表征.对[Bmim]PF6萃取废水中的硝基酚,以及离子液体的回收进行了初步研究.实验结果表明:邻硝基酚和对硝基酚在离子液体和废水两相的分配系数分别可达16和30以上,并随pH值的减小和离子液体用量的增大而增大;当pH<2时,两种硝基酚的萃取率都可达93%以上,可用调整pH值进行反萃的方法回收离子液体;当pH=12时,经5
Biodegradation of [bmim][PF6] using Fusarium sp
Esquivel-Viveros, A.;Ponce-Vargas, F.;Esponda-Aguilar, P.;Prado-Barragán, L.A.;Gutiérrez-Rojas, M.;Lye, G.J.;Huerta-Ochoa, S.;
Revista mexicana de ingeniería química , 2009,
Abstract: the increased use of ionic liquids in industry has led to the study of their biodegradability and toxicity to prevent contamination of the environment by these synthetic compounds. a fusarium strain was isolated and tested for its ability to tolerate and grow in the presence of [bmim] [pf6], a potential contaminant of wastewaters. the fusarium strain was able to grow in both surface and submerged liquid media using [bmim] [pf6] as the sole carbon source up to 19 and 21 g [bmim] [pf6] l-1, respectively. a membrane-aerated biofilm reactor was used for biodegradation studies of synthetic wastewaters. up to 80% biodegradation was observed after 28 days of incubation at 30 °c. this is the first time that [bmim][pf6] has been subjected to fungal biodegradation.
离子液体[bmim][PF6]与[moemim][PF6]结构微不均匀性以及微粘度的光谱探测
Spectroscopic Study of the Structural Heterogeneity and Microviscosity of [bmim][PF6] and [moemim][PF6] Ionic Liquids
 [PDF]

李博轩,郭前进(),夏安东()
- , 2015, DOI: 10.3866/PKU.WHXB201506101
Abstract: 室温离子液体由于其极低的蒸汽压、比较好的热稳定性和化学稳定性、良好的分子结构与性能的可设计性等优点,作为一种新型的环境友好溶剂在很多领域有着广泛的应用.对于离子液体的微观结构和微观性能的研究是设计新型离子液体以及扩展离子液体应用的关键.本文通过荧光探针分子香豆素153(C153)的转动动力学和对微观环境敏感的荧光探针分子1, 3-二(1-芘基)丙烷(BPP)的稳态荧光光谱,探测和表征了烷基取代的离子液体1-丁基-3-甲基咪唑六氟磷酸盐([bmim][PF6])和与其具有相似结构的醚键官能化的离子液体1-甲氧基乙基-3-甲基咪唑六氟磷酸盐([moemim][PF6])的微观结构和微粘度. C153探针分子在离子液体[bmim][PF6]中的转动过程具有快、慢两个组分表明离子液体[bmim][PF6]内部存在松散和紧密的两种结构微区;而C153探针分子在离子液体[moemim][PF6]中的转动动力学只存在一种过程,说明醚键的引入使得[moemim][PF6]内部趋于一种类型的微环境.通过C153探针分子的转动时间研究发现,醚键官能化的离子液体[moemim][PF6]的微粘度小于烷基链取代的离子液体[bmim][PF6],同时通过BPP探针分子的二聚体激基复合物(excimer)与单体(monomer)荧光发射强度的比值(IE/IM)研究也证明这一结果.醚键的引入使得离子液体[moemim][PF6]相对于离子液体[bmim][PF6],侧链的极性更大、柔顺性更好,同时醚键有可能作为氢键的受体与阳离子形成氢键从而削弱离子液体中阴、阳离子间的相互作用,使得离子液体[moemim][PF6]的微观环境比离子液体[bmim][PF6]更为均一,同时具有更小的微粘度.
Room temperature ionic liquids (RTILs), which have several special properties such as negligible vapor pressure, high thermal and chemical stability, good molecular structure and property designability, have received a great deal of attention, and have emerged as potential environmentally benign solvents. Therefore, a deep understanding of the solvent properties of RTILs, especially the microenvironment properties, is crucial to design new RTILs and extend their applications. The structural heterogeneities and local viscosities of the microenvironments of the ionic liquid [bmim][PF6] and the ether-functionalized ionic liquid [moemim][PF6] were investigated by the rotational dynamics of coumarin 153 (C153) and the excimer-to-monomer fluorescence emission intensity ratio (IE/IM) of 1, 3-bis(1-pyrenyl)propane (BPP). The rotational dynamics of C153 shows that there are incompact and compact domains within the heterogeneous structure of [bmim][PF6], resulting in fast and slow components of C153 rotational dynamics. The rotational dynamics of C153 shows that there is mainly one type of microenvironment in [moemim][PF6]. The C153 rotation time constants show that the microviscosity of [moemim][PF6] is lower than that of [bmim][PF6], and this result is confirmed by steady-state fluorescence measurement with the BPP microviscosity probe. The side chain of [moemim][PF6] is more polar and more flexible than that of [bmim][PF6], and the oxygen of the ether group could act as a hydrogen bond acceptor and interact with the cations of the ionic liquid, which possibly reduces the electrostatic attraction between the cations and anions in the ionic liquid and leads to the lower structural heterogeneity and microviscosity of [moemim][PF6]
L-proline catalyzed efficient and clean synthesis of polysubstituted benzenes in the ionic liquid [bmim]PF6
Jain Shubha,Keshwal Balwant S.,Rajguru Deepika
Journal of the Serbian Chemical Society , 2012, DOI: 10.2298/jsc111211067j
Abstract: A clean and efficient synthesis of polysubstituted benzenes has been developed via sequential vinylogous Michael addition and nucleophilic cyclization reactions of arylethylidenemalonodinitriles with arylidenemalo-nodinitriles in ionic liquid [bmim]PF6 catalyzed by L-proline.
室温离子液体[Emim][PF6]和[Bmim][PF6]压致相变的拉曼散射研究  [PDF]
朱祥,王永强,王征,程学瑞,袁朝圣,陈镇平,苏磊
高压物理学报 , 2013, DOI: 10.11858/gywlxb.2013.02.013
Abstract: 室温条件下,采用拉曼光谱仪和四柱型金刚石压砧(DAC),对两种室温离子液体的压致相变进行了详细的研究。实验表明,对于常压下为固态的1-乙基-3-甲基咪唑六氟磷酸盐(Emim][PF6],C6H11F6N2P)离子液体,压力增加到约0.86GPa时,发生固-固相变;对于常压下为液态的1-丁基-3-甲基咪唑六氟磷酸盐([Bmim][PF6],C8H15F6N2P)离子液体,压力增加到约0.62GPa时,发生液-固相变,增加到约1.45GPa时,发生固-固相变。此外,还对[Bmim][PF6]加压后的卸压过程进行了详细分析,结果表明:离子液体[Bmim][PF6]在0~2GPa范围内的压致相变是可逆的。
Asymmetric Glyoxylate-Ene Reactions Catalyzed by Chiral Pd(II) Complexes in the Ionic Liquid [bmim][PF6]  [PDF]
Xi Jun He,Zhen Lu Shen,Wei Min Mo,Bao Xiang Hu,Nan Sun
International Journal of Molecular Sciences , 2007, DOI: 10.3390/i8060553
Abstract: The room temperature ionic liquid [bmim][PF6] was employed as the reactionmedium in the asymmetric glyoxylate-ene reaction of α-methyl styrene (4a) with ethylglyoxylate using chiral palladium(II) complexes as the catalysts. [Pd(S-BINAP)(3,5-CF3-PhCN)2](SbF6)2 (1b) showed the highest catalytic activity. Under the reaction conditionsof 40 oC, 0.5 h, and 1b/4a molar ratio of 0.05, ethyl α-hydroxy-4-phenyl-4-pentenoate wasobtained in excellent chemical yield (94 %) with high enantioselectivity (70 %). Otherα-hydroxy esters can also be obtained in high chemical yields and enantioselectitiesthrough the glyoxylate-ene reactions of alkenes with glyoxylates catalyzed by 1b in[bmim][PF6]. Moreover, the ionic liquid [bmim][PF6] which contained the palladium(II)complex could be recycled and reused several times without significant loss of the catalyticactivity.
[omim][PF6]萃淋树脂的制备及对萘吸附机制的研究  [PDF]
戴宁,张凤君,陈继,牧辉,李隋,吕任生
环境科学 , 2009,
Abstract: 将离子液体[omim][PF6]以液膜的形式固定在大孔吸附树脂上,制备萃淋树脂,研究其对水相中萘的吸附及影响因素.结果表明,离子液体[omim][PF6]萃取萘的过程,萘主要分配在[omim]+的疏水饱和碳链上;树脂和离子液体质量比为10∶1和20∶1的萃淋树脂,[omim][PF6]在水相中的溶解明显小于2∶1和5∶1的萃淋树脂;不同质量比萃淋树脂对萘的饱和吸附量大小为10∶1萃淋树脂>20∶1萃淋树脂>树脂,对吸附等温线的拟合结果表明,树脂对萘的吸附更符合Freundlich吸附等温式,而萃淋树脂对萘的吸附则更符合Langmuir吸附等温式.不同温度萃淋树脂对萘的饱和吸附量大小为:20℃>15℃>25℃,随着pH的升高饱和吸附量下降,随着无机盐浓度的提高饱和吸附量均有提高;正交实验确定的最佳条件为:温度=30℃、pH=3、NaCl浓度=2000 mg·L-1,其中pH值是最主要的影响因素.
The Henry Reaction in [Bmim][PF6]-based Microemulsions Promoted by Acylase  [PDF]
Wen-Jian Xia,Zong-Bo Xie,Guo-Fang Jiang,Zhang-Gao Le
Molecules , 2013, DOI: 10.3390/molecules181113910
Abstract: An environmentally-friendly, enzyme-promoted procedure for the Henry reaction was first studied using water-in-[Bmim][PF 6] microemulsions as reaction medium. The Amano acylase from Aspergillus oryzae showed better catalytic activity for the addition reactions of nitromethane with a series of aromatic aldehydes, and a highest yield of 90% was obtained.
Laser photolysis study of anthraquinone in binary mixtures ofionic liquid [bmim][PF6] and organic solvent  [PDF]
Guanglai Zhu,Jingjing Xu,Guozhong Wu,Hongping Zhu,Dewu Long,Shimou Chen,Side Yao
International Journal of Molecular Sciences , 2006, DOI: 10.3390/i7120590
Abstract: Photochemical properties of the ionic liquid (RTIL) 1-butyl-3-methylimidazoliumhexafluorophosphate [bmim][PF6] and its binary mixed solutions with organic solvent(DMF and MeCN) were investigated by laser photolysis at an excitation wavelength of 355nm, using anthraquinone (AQ) as a probe molecule. It was indicated that the triplet excitedstate of AQ (3AQ*) can abstract hydrogen from [bmim][PF6]. Moreover, along with thechange of the ratio of RTIL and organic solvent, the reaction rate constant changes regularly.Critical points were observed at volume fraction VRTIL = 0.2 for RTIL/MeCN and VRTIL =0.05 for RTIL/DMF. For both systems, before the critical point, the rate constant increasesrapidly with increasing VRTIL; however, it decreases obviously with VRTIL after the criticalpoint. We conclude that the concentration dependence is dominant at lower VRTIL, while theviscosity and phase transformation are dominant at higher VRTIL for the effect of ionic liquidon the decay of rate constant.
离子液体[bmim][pf6]与[moemim][pf6]结构微不均匀性以及微粘度的光谱探测  [PDF]
李博轩,郭前进,夏安东
物理化学学报 , 2015,
Abstract: 室温离子液体由于其极低的蒸汽压、比较好的热稳定性和化学稳定性、良好的分子结构与性能的可设计性等优点,作为一种新型的环境友好溶剂在很多领域有着广泛的应用.对于离子液体的微观结构和微观性能的研究是设计新型离子液体以及扩展离子液体应用的关键.本文通过荧光探针分子香豆素153(c153)的转动动力学和对微观环境敏感的荧光探针分子1,3-二(1-芘基)丙烷(bpp)的稳态荧光光谱,探测和表征了烷基取代的离子液体1-丁基-3-甲基咪唑六氟磷酸盐([bmim][pf6])和与其具有相似结构的醚键官能化的离子液体1-甲氧基乙基-3-甲基咪唑六氟磷酸盐([moemim][pf6])的微观结构和微粘度.c153探针分子在离子液体[bmim][pf6]中的转动过程具有快、慢两个组分表明离子液体[bmim][pf6]内部存在松散和紧密的两种结构微区;而c153探针分子在离子液体[moemim][pf6]中的转动动力学只存在一种过程,说明醚键的引入使得[moemim][pf6]内部趋于一种类型的微环境.通过c153探针分子的转动时间研究发现,醚键官能化的离子液体[moemim][pf6]的微粘度小于烷基链取代的离子液体[bmim][pf6],同时通过bpp探针分子的二聚体激基复合物(excimer)与单体(monomer)荧光发射强度的比值(ie/im)研究也证明这一结果.醚键的引入使得离子液体[moemim][pf6]相对于离子液体[bmim][pf6],侧链的极性更大、柔顺性更好,同时醚键有可能作为氢键的受体与阳离子形成氢键从而削弱离子液体中阴、阳离子间的相互作用,使得离子液体[moemim][pf6]的微观环境比离子液体[bmim][pf6]更为均一,同时具有更小的微粘度.
Page 1 /100
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.